Urbanization and plant invasion alter the structure of litter microarthropod communities

Anthropogenic activity underpins the creation of urban ecosystems, often with introduced or invasive species playing a large role in structuring ecological communities. While the effects of urbanization on charismatic taxa such as birds, bees or butterflies have received much attention, the impacts on small and inconspicuous organisms remain poorly understood. Here, we assess how the community structure of leaf litter-inhabiting microarthropods in city parks varies along an urbanization gradient in Toronto, Canada. At each park, we established paired forest understory plots which were either dominated by native vegetation or dog-strangling vine (Vincetoxicum rossicum), an invasive species that is spreading throughout northeastern North America and abundant in urban areas. We compared microarthropod richness, abundance, and diversity in ecological traits between invaded and non-invaded plots as well as compositional dissimilarities among plots across the urbanization gradient. We r...